Predictive model



I have a dataset of an inventory that grows in some intervals of time and decreses hugely in others. I am trying to figure out a way to calculate how many days is needed for the inventory to achieve the red line based on the growing trend of the periods where the inventory increases.  I am a newbie in Spotfire and having a hard time with this. The idea is to plot new predicted bars like a forecast. Do you have any suggestion? Some material that I can study and apply to this problem ? Thanks!




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